The study of the effects of electromagnetic radiations (450 MHz, amplitude modulation 0-90%, 0.1-10 mW/cm2) on behavioral performances and brain neurochemistry of laboratory animals, (monkeys, cats and chickens) will be continued, using the field exposure techniques developed and tested in this laboratory during the 1974-75 research period. Internal dosimetry studies and development of recording electrodes will be pursued in chronic and acute preparations. Theoretical models of brain tissues will be developed to provide basis for interpretation of the experimental results and possibly new designs of brain tissue simulation.